Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can state the condition for a system’s velocity to change, and explain why a constant velocity, including zero, needs no net force. (Guide: “When does velocity change?”)
- I can explain why internal forces cannot change the motion of a system’s center of mass. (Guide: Worked example 2; Practice Q2, Q7)
- I can explain why the acceleration points along the net force, even when the velocity points another way. (Guide: “The law and its parts”; Figure 1)
- I can explain why the velocity keeps the value it has reached when the net force drops to zero. (Guide: Worked example 3; Figure 2)
Calculation
- I can apply ΣF_x = m a_x and ΣF_y = m a_y to forces at angles, and give the size and direction of a. (Guide: Worked example 1; Practice Q3)
- I can predict the factor by which a changes when the net force and the mass both change. (Practice Q1, Q5(e))
- I can find an internal force, such as a tension, by applying the law to a smaller system. (Guide: Worked example 2; Practice Q5(b))
- I can integrate a time-dependent net force to find v_x(t), including v_x0, and find when the velocity is greatest. (Guide: Worked example 3; Practice Q4)
- I can derive the acceleration of a connected system in symbols and check it with a limiting case. (Practice Q5)
Reasoning
- I can plan a cart experiment that tests a ∝ F or a ∝ 1/m, saying what to keep constant and how to make friction negligible. (Guide: “Testing the law in the lab”; Practice Q6)
- I can choose what to plot to get a straight line, and say what its slope means. (Practice Q6)
- I can use the center-of-mass velocity to judge a claim about whether a system speeds up. (Practice Q7)
All ticked? Move on to Topic 2.6, Gravitational Force, or return to the course roadmap.